ASTPP Customization freeswitch

I need to customize some litle aspects of the GUI of the ASTPP Billing. This is the customization that I need: 1 - Show active calls on clients login 2 - Show negative "balance" for post-paid clients, exactly like the PRE-PAID clients, not the "credit limit" information. 3 - Create a random callerID for specific sip devices, like that: If I call to the number 55 48 996843116, the system need to generate a caller ID with the same 4 initial digits: 5548 and a random mobile number like: 9876XXXXX. So, If I set for a specific sip device a callerid like "random" generate this style of callerID for the call. I have priority on the Random CallerID, we can discuss about just this item, this is very important to me. The others itens are just cosmetic, but this is really important.